▎ 摘　　要

NOVELTY - The preparation method of composite anode material involves mixing graphene dispersion, graphite powder and water, ultrasonically dispersing and homogeneously transferring to high-pressure reaction vessel, filling carbon dioxide gas with high-pressure reaction vessel and then depressurizing, mixing lithium carbonate, lithium hydroxide, ammonium dihydrogen phosphate, phosphoric acid, iron acetate and citric acid to obtain mixed aqueous solution, mixing graphene dispersion liquid with lithium iron phosphate precursor solution, heating, drying, and calcining. USE - The method is useful for preparing composite anode material, which is useful for lithium battery. ADVANTAGE - The method enables preparation of composite anode material with excellent stability. DETAILED DESCRIPTION - The preparation method of composite anode material involves mixing graphene dispersion, graphite powder and water in weight ratio of 1:50000-1:500, ultrasonically dispersing and homogeneously transferring to high-pressure reaction vessel at temperature of 50 degrees C, filling carbon dioxide gas with high-pressure reaction vessel at pressure of 100 atm for 40 minutes and then depressurizing at rate of 50 ml/second, mixing 1.2-2 mol/l lithium carbonate, 0.8-1 mol/l lithium hydroxide, 1.4-2 mol/l ammonium dihydrogen phosphate, 0.6-1 mol/l phosphoric acid, 2-3 mol/l iron acetate and 0.5-2.5 mol/l citric acid to obtain mixed aqueous solution, mixing graphene dispersion liquid with lithium iron phosphate precursor solution in volume ratio of 1:20-1:9, heating at 70 degrees C, drying the mixture under inert atmosphere, and calcining at 650-750 degrees C for 6-12 hours.